Automatic guiding apparatus



Feb. 23, 1965 T. F. HENEBRY, I 3,170,423

Ammo comm; APPAArus 2 Sheets-Sheet 1 Filed April 24, 1961 INVENTOR. Thomas F Henebr'y ATTORNEY Feb. 23, 1965 1-. F. HENEBRY 3, 7

AUTOMATIC GUIDING APPARATUS Filed April 24, 1961 2 Sheets-Sheet 2 '5 uvmvron. 0 ,7 69.3 Thomas E Henebry 14 T TORNE Y comes th above-noted defects i d States Patent h ()flice 3,170,423 Patented Fe b. 23, 1965 AUTOMATIC GUIDING APPARATUS Thomas F. Henebry, Bethel, Conn., assignor to Ernest M. Jl'lnkins, Monroe, Conn. Filed Apr. 24,1961, Ser. No. 105,193 13 Claims. (Cl. 112- -2) devices have not been sufiiciently satisfactory to be universally acceptable. Thus the proposed devices have had one or more of the following deficiencies which prevented their acceptance in replacing hand operations. The material was not fed to the needle the same as in a hand operation where the material is pivoted substantially about'the needle axis and stitch formation and seam appearance were accordingly adversely affected; the machines were complicated and expensive mechanism generally having complex cam and gear configurations; the positioning and removal of work from the machines was time consuming; and the machines were not sufiiciently flexible to enable the stitch path to bechanged by simple changes in the guiding apparatus.

It is'accordingly' an object of the present invention to provide a guiding apparatus for guiding work pieces automatically along a predetermined contour path and which, when employed with a conventional sewing machine, overin the heretofore known devices.

. Another object of the present invention is to provide an automatic guiding apparatus in which work pieces to be stitched are merely placed at a loading station and the guiding apparatus automatically grasps the work pieces to guide them along the selected path and after finishing the path, automatically releases them.

A further object of the present invention is to provide an automatic guiding apparatus that is simple in construction, durable in use, easily changed to guide work pieces along a different path and requires very little skill on the part'of the operator. g

In carryingout the above objects, the automatic guiding apparatus of the present invention is hereinafter disclosed in its specific embodiment as being used with a sewing machine to guide work pieces to the sewing machine stitching mechanism to have the formed stitches be in a preselected path. The guiding apparatus includes a work holder that is mounted for universal movement in a horizontal plane slightly above a table which supports the sewing machine. Work pieces are positioned on a work piece loading station formed in the table top and the work holder is caused to move over the work pieces at the load ing station and grasp and hold'them by forming a vacuum in the work holder. With thepiecesfirmly held by sucfrom the holder and the above cycle of operations repeated on the subsequent work pieces. Y

Other featuresand advantages will hereinafter appear.

In the drawing: 1

FIG. 1 is a perspective vie'w'of the automatic guiding apparatus of the present invention as employed with a 'sewing machine. a

FIG. 2 is a diagrammatic section taken substantially on the line line 22 of FIG. 1. r 7

FIG. 3 is an electrical schematic diagram of the interconnection of the electrical components of guiding apparatus'of the present invention; t

Referring to th drawing, the automatic guiding apparatus is.generally indicated by the reference numeral: 10 and while it may be used with other machines, such as a heat seaming machine, it is hereinafter disclosed in conjunction with a sewing machine 11. The sewing machine is preferably of the chain stitch type and has a needle 12 that is reciprocated by rotation of a hand wheel pully l3 driven by a belt 14- which in turn is actuated by a conventional sewing machine driv mechanism 15 having a transmitter clutch solenoid 16,.that when energized drives the belt 14 and when de-energized brakes the'belt 14, and hence the sewing machine. Adjacent the needle is a presser foot bar 17 and while the presser foot is not shown, it may have the usual configuration. Additionally, the sewing machine may have the usually adjustable length feeding mechanism 172a, work plate with stitching form- .will be hereinafter apparent.

The work holder is eccentrically fastened to the bottom vend of a tubular shaft 22 that is supported in a bearing 23 to enable pivoted movement ofthe shaft and hence the work holder. Avertical cylindrical support 24 is secured to the back edge of the table 18 and rotatably positioned thereon for rotation about the vertical axis of the support 24 is a bearing 25 that is supported by a collar -26. The

bearing 25 supports for only longitudinal axialmovement a tubular shaft 27 which by any well-known construction (not shown) prevents rotation of the shaft 27 and which has an end secured to the bearing 23. Accordingly, the

work holder may be pivoted by pivotal. movement of the .shaft 22, may move backwards and forwards by the shaft 27 longitudinally moving in the bearing 25 and may move sideways by rotation of the bearing 25 about the vertical axis of the support 24., 'While all these movements may Occur simultaneously, it will be clear that these movements of the work holder in the specific embodiment shown, are in a horizontal plane that is spaced slightly above the horizontal-top of the table 18 and hence the work holder is mounted for universal movement in a plane.

The shaft 22 extends above the bearing 23 and is secured to a telescoping shaft 28, as by a'universal joint 29 while the other end ofthe shaft 28, also by a'universal joint 30, is connected to the output shaft of an electric motor 3l, that may be supported in any desired manner.

. The motor 31 is of the type shown in US. Patent 2,105,-

513 and may, by appropriate energization, as will be hereinafter set forth, be rotated slowly in either direction or maintained stationary. While a specific motor is herein disclosed, it will be appreciated that the invention is not to be limited thereto since other driving reversible and stationary driving mechanisms may be employed, if desired.

The path followed by the work holder is determined by a shape of a camm-ing surafce which herein is the periphery of a cam 32 that is secured to the shaft 22. A friction wheel or follower 33 mounted on a stub shaft 34 frictionally engages the periphery of the cam 32 at a point (or a line) according to the present invention, that is vertically aligned with the axis of the needle as indicated by a center line 35. The shaft 34, and hence the wheel 33, .is rotated by a belt 36 connected to the swing machine pully 13 and to a shaft 37 through a one-way clutch pully- 38 such that the wheel 33 is rotated whenever the swing machine is operating. To drive the wheel 33 whenever the swing machine is not operating, there is an electric motor 39' connected to the shaft 37 by means of a belt 40 and a one-way clutch pully 41. A

coil spring 42 on the support 24 bears against the heartermined by the shape of the cam 32. Whenever no rotational movement is required, then the work pieces are held against rotation. Referringlto FIGS. =1 and 2, there is provided a sensing means generally indicated by the reference number 43 that includes a forward sensing element 44 and a rearward sensing element 45, that are mounted in support member 46 for longitudinal movement. The two elements have ends 47 and 48 respectively that are spring urged as by springs 49 and 50 respectively against the priphery of the cam 32. The two ends are spaced quite closely together with the end 47 being just slightly in front of the needle axis 35, while the end 48 is slightly in back of the axis 35.

It will be clear with the above construction that the cam priphery immediately before and after the needle axis line engagement with the wheel 33 is in engagement with the ends 47 and 48 and if the ends '47 and 48 pro jectthe same distance outwardly from the support, then the part of the work pieces just in front of the needle is aligned with the normal direction of machine feed as it should be. Deviation or canting of the work pieces with respect to the normal direction of feed is sensed by the sensing elements by the element ends projecting outwardly different distances, as also occurs when there is a curve in the path of stitching. To correct the deviation and to stitch a curve, the sensing elements provide for rotation of the shaft 22 to move the work pieces to the correct feeding position.

Accordingly the front sensing element 44 has secured thereto two normally closed single pole,. single throw microswitches 5 1 and 52, that are aligned, with the actuating arm of switch 51 being towards the wheel 33 while the actuating arm of the switch 52 being away from the wheel 33 or in the opposite direction. The rear sensing element has an end formed into a U shape with two actuators 53 and 54 mounted on the legs of the U shape to project inwardly to he engageable with the actuating arm of the switches 51 and 52 respectively that are positioned between the actuators. Thus relative movement of a predetermined amount between the two sensing Thus there are normally closed micro-switches Stand 52 connected to the motor 31 between a pair of input lines '55 and 56 that are connectable to a source of 110v, 60

cycle alternating current. An on-oif switch 57 is located in the line 55.

The motor 39 is connected to the input lines through a normally closed relay 58. Reference numeral 59 indicates the selenoid actuated transmitter clutch of a conventional sewing machine drive motor 60 and the sole noid 59, both generally indicated by the reference numerals 15 and 16 respectively in FIG. 1, when energized, drives the sewing machine by' engagement with the continuously driven motor 60 and when de-energized, brakes the sewing machine. The solenoid 59 is connected across the input lines in series with a normally open switch 61. y V

As shown in FIG. 1, the switch 61 is mounted to be actuated by a cam ridge 62 formed on the upper surface of the cam 32 such that when the ridge engages the switch arm, the switch is closed, energizing the solenoid 59 to drive the sewing machine. The relay 58, however, is connected in parallel with the solenoid 59 to the switch 61 so that whenever the switch 61 is closed, the motor 39 is de-energized while on the other hand, when the switch 61 is open the motor 39 is energized to drive the shaft 37 and hence the wheel 33 and cam 32.

For effecting the grasping, holding and releasing of the work pieces, there is provided a normally open switch 63, connected in series with a solenoid actuated valve 64 across the input lines. The switch 63 is also mounted to be actuated by a cam ridge 65, formed on the top surface of the cam 32. The solenoid valve 64 is contained within a box 66 secured to the table 18 (FIG. 1) to control a valve to connect a source of air pressure to which a tube 67 is connectible with either a flexible suction tube 68 or a flexible pressure tube 69. The ends of these two tubes terminate in the tubular shaft 27. The suction tube by directing air under pressure from the source outwardly from the end of the shaft 27 acts as an aspirator to create a vacuum therein which extends through the shaft 27, the shaft 22 to the apertures 21 formed in the bottom surface of the work holder 19. The vacuum is sufficient to hold the workpieces. To release the work pieces, the vacuum is destroyed by the switch 63 being opened at. the end of the cam ridge 65, de-energizing the solenoid valve 64 to connect the source tube 67 to the pressure tube 69 for introducing air pressure into the shaft 27 and hence to the apertures 21. I

In the operation of the apparatus, an operator places the two (or more) pieces of work that are to be stitched together along the stitch patch determined by the periphery of the cam 32, in a work station 70, formed as a recess in the top of the table 18. The work pieces shown have the shape of a mans shirt cuff, and are substantially recantuglar, having two curved corners with stitching to extend about a side 71, a corner 72, the front edge 73, a corner 74, and the other side 75. The sides 76 and 77 of the work station serve not only to aid in station 70, energization of the input lines is effected by closing line switch 57. The suction solenoid 64 is deenergized as is the sewing machine transmitter clutch solenoid 59 by the switch 61 being open but since the relay 58 is of the normally closed type, the motor 39 is energized to rotate the cam and hence the work holder. Moreover, the motor 31 is energized through both switches 51 and 52 and hence remains stationary. As the wheel 33 rotates the cam any deviation of the earn from the path selected by its periphery as sensed by the sensing elements will open either switch 51 or 52 to cause the motor 31 to rotate the shaft 22 to correct for the deviation and which, upon being corrected, the motor 31 stops to hold the shaft non-rotating.

When the work holder is positioned over the work station, the cam ridge 65 closes the switch 63 which causes air to flow out of suction tube 68 to create a vacuum in the work holder which sucks the work pieces off the work station against the holder (holes 78 may be provided in the table to provide for air relief under the work pieces). Carrying the work pieces, the work holder moves around until the point where the work piece is just before the needle at which time the switch 61 is actuated, de-energizing motor 39 and actuatingthe solenoid clutch 59 to drive the sewing machine, to form a chain stitch and also drive the wheel 33. The cam is moved by the wheel 33 as stitching prognesses on the work pieces in the path determined by the peripheral contour of the cam 32. If the cam 32 should deviate or cant from the normal sewing machine line of feed to a deviated position, for example indicated by a dotted line 79 in FIG. 2, then the switch 51 is actuated by the end 47 projecting further than the end 48 to cause counterclockwise rotation of the shaft 22 to correct for the deviation. As soon as the deviation has been corrected and sensed by'the ends 47 and 48 being equally projecting outward in engagement with the cam 32, the normal non-actuating position of the elements 44 and 45, the motor 31 stops rotating.

It will be appreciated that rotation of the shaft 22 causes the cam to rotate and that the center of the rotation is at the needle axis since the rotation is about the line engagement of the cam 32 and the wheel 33 which coincides with'the needle axis.

The same occurrence, i.e. rotation of the motor 31, occurs when a curve appears in the cam periphery, since the position of the ends will be varied by the changing shape of the cam periphery, causing the motor 31 to be energized in a manner that rotates the shaft 22.

At the completion of the stitching, which, if a chain stitch, may include a short chain string extending from the end of the work pieces, the cam ridge 62 ends, opening the switch 61 which opens the solenoid clutch 59 of the sewing machine, stopping it and simultaneously energizing the motor 39 to drive the wheel 33 and hence the cam 32.

Further movement of the cam 32 causes the cam ridge 65 to end, opening the switch 63 to cause air pressure to be introduced through the pressure tube 69 to destroy the vacuum and release the work pieces.

During the above cycle, the operator has had time to place the next work pieces at the loading station and, as the work holder is moved to be positioned thereover, the above cycle of operationwill be repeated.

Referring to FIG. 2, there is diagrammatically shown the path of the movement of the cam 32, where small reference characters (a through h) are used to indicate various points of the cam that are engageable withthe wheel 33, the corresponding position of the shaft 22 for each point when it engages the wheel 33 is indicated by the same letter only capitalized,.while a prime capitalized letter'indicates the broken line position of the cam. Thus reference characters A and A are for the full line position of thecam and shaft for the point a on the cam where the front edge 73 is being stitched, Band B are I for the next position b which is at the start of the rounded corner 74, C and C' the point e which is the end of the corner 74, D and D the end of a straight portion constituting the side 75 and where the work piece is released, E and E the start of a rounded corner, F and F the end of the corner where the work holder is. positioned over the work piece loading station 70, G and G the start of the rounded corner 72 of the work piece and H and H the end of the corner 72. To show the path of movement between the various positions of the shaft, light lines are employed with arrows showing the direction of the movement along the lines. Throughout this movement of sence if there is a deviation of the cam from the selected path and operate to rotate the is eliminated,

While there has been described a friction drive between the wheel 33 and the cam 32, it will be appreciated to those skilled in the'art that a different driving engagement maybe used, as for example, making the wheel 33 a gear and forming the periphery of the cam 32 as a rack, at least for the portion that would engage the wheel 33.

While the work pieces are being stitched, the speed of the periphery of the cam is the speed of the work pieces passing under the needle. Normally, when both the; wheel 33 and the feed dogs are driving the cam and movingthe work pieces, then the two speeds have to be the same. In some instances, it may be desirable to elimishaft 22 until the deviation hate the feed dogs entirely depending on the wheel 33 to do all the moving of the cam and work holder.

In other instances, the wheel 33 may be free running ,(as by eliminating the belt 36) and the feed dogs do all the driving. Or again, with both driving some slippage may be permitted between the wheel and the cam (as by decreasing the tension of spring 42) to let'the feeddogs of the sewing machine control the speed of the movementbut yet receive assistance in driving from the wheel 33. In each of the above instances, however, it will be clear that the wheel 33 in a sense functions as a follower for the cam 32.

The switches 51 and 52 have been disclosed as the normally closed type so that the motor 31, when both switches are closed, will be energized in its stopped or hold position. However, it is within the scope of the present invention to employ normally open switches and depend on the residual magnetism of the motor to main: tain it in.the hold or non-rotation position. Moreover, while the motor 31 may be energized by alternating current that has a lower frequency than the 60 cycle source shown if it is desired to decrease its speed and increase its torque.

While the presser foot maybe operated at desired times I by use of a cam ridge and switch operating the well known solenoid operated presser foot lifting mechanism, the present invention contemplates setting the height of the presser foot so that no lifting thereof is required to introduce the work pieces thereunder. g

It accordingly will be appreciated that there has been disclosed an automatic apparatus which enables, when employed in conjunction with a sewing machine, for the stitching of a predetermined path in work pieces which may include both straight and contour portions. The work pieces are simply, yet effectively, grasped in a known relationship to the apparatus by the accurate positioning of the work pieces in a loading station and having the apparatus employ a vacuum as the grasping and holding means. The release of the work pieces is easily effected after the stitching operation by the destroying of the vacuum.

During the stitching operation, the work pieces are moved as if by hand in that rotative movement of the work pieces is always about the axis of the needle and the line of stitches at the needle is maintained in the direction of the normal sewing machine feed, irrespective of the change in contour of the predeterminedpath. Any

deviation from the path is sensed and the work pieces are pivoted about the needle axis until the deviation is eliminated. s

Variations and modifications may be made Within the scope of the claims and portions of theimprovements may be'usedwithout others. I

I claim: I 1. An apparatus for-guiding work past a work station along a predetermined path including an arcuate length comprising a work holder adapted to hold work, means supporting the work holder for free lateral and longitudinal and rotational movement in a plane, said work station including a needle, first means for moving the work holder, past the needle, means for sensing and proconnected to a source of external energy for moving the work holder to have the work pivot about the needle and means connecting the sensing means to the second work holder moving means for moving the work holder upon receipt of a signal from the sensing means with the work holder supporting means permitting and accommodating an lateral and longitudinal movement of the work holder as it pivots.

2. An apparatus for guiding work past a work station along a predetermined path with the work station having a normal feed path and with said work station including a needle comprising a work holder adapted to hold work, means supporting the work holder for free lateral and longitudinal movement in a plane and rotational movement about the needle, first means for moving the work past the work station, said means supporting the work holder and first means for moving the work causing said work holder to traverse a path which may deviate from the normal feed path, means for sensing and producing a signal indicative of the length of work approaching the work station deviating from the normal feed path, second means independent of the first work moving means adapted to be connected to a source of external energy for moving the work holder to have the work pivot about the needle and means connecting the sensing means to the second work holder moving means for moving the work holder by said second work holder moving means upon receipt of a signal from the sensing means to align the length of work approaching the work station with the normal feed path with the work holder supporting means permitting and accommodating any lateral and longitudinal movement of the work holder as it pivots.

3. An apparatus for guiding work past a stitch forming station including a needle along a predetermined path with said stitch forming station having a normal feed path comprising a work holder adapted to hold work, means mounting the Work holder for free lateral and longitudinal and rotational movement, first means for moving the work along the predetermined path, path means moving with the work holder, abutment means positionedto engage the path means at a point in alignment with the needle, means for urging the path means against the abutment means, said means mounting the work holder and said means for moving the work causing said work holder to traverse a path which may deviate from the normal feed path, means for sensing and producing a signal indicative of the deviation of a point of the path means ahead of the point of engagement of the path means and the abutment means with respect to the normal feed path, second means independent of the first work moving means adapted to be connected to a source of external energy for ro tating the work holder about the point of engagement and means connecting the sensing means to the work holder rotating means for rotating the Work holder upon receipt of asingal from the sensing means with the work holder mounting means permitting and accommodating any lateral and longitudinal movement of the work holder as it rotates.

4. An apparatus for use with a sewing machine for guiding work past the needle along a predetermined path comprising a work holder adapted to hold work, means mounting the work holder for free lateral and longitudinal movement and rotational movement, means for moving the work holder, cam means mounted for movement with the work holder and having a camming surface defining the predetermined path, follower means positioned to engage the camming surface at a point in alignment with the needle, means urging the cam means against the follower means, means for sensing and producing a signal indicative of the deviation of a point of the camming surface on one side of the point of the camming surface engaging the follower means with respect to a point on the other side, means for rotating the work holder and means connecting the sensing means to the work holder rotating means for rotating the work holder upon receipt of a signal from the sensing means with the work holder supporting means permitting and accommodating any lateral and longitudinal movementof the work holder as it rotates.

5. In combination with a sewing machine having a needle and a normal feed path, an apparatus for guiding work past the needle along a predetermined path comprising a work holder adapted to hold work, means mounting the work holder for free lateral and longitudinal movement and rotational movement, means for moving the work holder, path means mounted for movement with the work holder, abutment means engaging the path means at a point in alignment with the needle, means urging the path means against the abutment means, means for sensing and producing a signal indicative of the deviation of a point of the work approaching the needle from the normal machine feed to the needle, means for rotating the work holder to pivot the work about the needle and means connecting the sensing means to the work holder rotating means for rotating the work holder upon receipt of a signal from the sensing means with the work holder supporting means permitting and accommodating any lateral and longitudinal movement of'the work holder as it rotates.

6. The invention as defined in claim 5 in which there is provided a source of electrical energy and a means connecting the source to the sensing means, and in which the sensing means produces an electrical signal that is different for when a deviation is sensed than when no deviation is sensed.

7. The invention as defined in claim 5 in which the sensing means signal is an electrical signal having one value for deviation in one direction and a different value for deviation in the opposite direction and in which the means for rotating the work holder rotates in one direction for one value of signal and rotates in the other direction for the different value of signal.

8. The invention as defined in claim 5 in which a support is provided at least at one position beneath the path ofmovement of the work holder and means defining a work loading station at the position.

9. The invention as defined in claim 5 there is pro vided means for creating a vacuum connected to the work holder and in which the work holder includes a surface engageable with the work with the surface being formed with apertures therein to enable work to be held by the work holder by suction.

l0. The invention as defined in claim 5 in which there is provided a support located at a position beneath the path of movement of the work holder, a work loading station located at said position, said-work holder including a surface engageable with the work with the surface being formed with apertures therein and means for applying a vacuum to said apertures when the Work holder is positioned over the work loading station.

13. An apparatus for guiding'work past a work station having a needle along a predeterminedpath comprising a work holder adapted to hold work, means supporting the Work holder for free lateral and longitudinal movement in a plane and rotational movement about the needle, first means for advancing the Work holder holding the work past the working station, said means supporting the work holder and first means causing said work holder to traverse a path which may deviate from the predetermined path, means for sensing and producing a signal indicative of a deviation of the path of the work holder from the predetermined path, second means for moving the work holder independent of the first means and adapted to be connected to a source of external energy and means interconnecting said second means with the work holder and said means for sensing and producing a signal, said second means being actuated upon receipt of a signal to cause a rotational movement of the work holder about the needle to overcome the deviation with the work holder supporting means permitting and accommodating any lateral and longitudinal movement of the work holder necessary to overcome the deviation.

References Cited in the file of this patent UNITED STATES PATENTS Mayo Dec. 18, 1928 Levine Oct. 9, 1951 Berry May 25, 1954 Abel Apr. 7, 1959 Eisengrein June 7, 1960 Haldemann et al. Aug. 9, 1960 Cordier Feb. 14, 1961 Mulligan et al. Jan. 8, 1963 FOREIGN PATENTS Great Britain Sept. 7, 1960 

1. APPARATUS FOR GUIDING WORK PAST A WORK STATION ALONG A PREDETERMINED PATH INCLUDING AN ARCUATE LENGTH COMPRISING A WORK HOLDER ADAPTED TO HOLD WORK, MEANS SUPPORTING THE WORK HOLDER FOR FREE LATERAL AND LONGITUDINAL AND ROTATIONAL MOVEMENT IN A PLANE, SAID WORK STATION INCLUDING A NEEDLE, FIRST MEANS FOR MOVING THE WORK HOLDER PAST THE NEEDLE, MEANS FOR SENSING AND PRODUCING A SIGNAL INDICATIVE OF THE APPROACH OF THE ARCUATE LENGTH OF THE PATH TO THE NEEDLE, SECOND MEANS INDEPENDENT OF THE FIRST WORK HOLDER MOVING MEANS ADAPTED TO BE CONNECTED TO A SOURCE OF EXTERNAL ENERGY FOR MOVING THE WORK HOLDER TO HAVE THE WORK PIVOT ABOUT THE NEEDLE AND MEANS CONNECTING THE SENSING MEANS TO THE SECOND WORK HOLDER MOVING MEANS FOR MOVING THE WORK HOLDER UPPON RECEIPT OF A SIGNAL FROM THE SENSING MEANS WITH THE WORK HOLDER SUPPORTING MEANS PERMITTING AND ACCOMMODATING ANY LATERAL AND LONGITUDINAL MOVEMENT OF THE WORK HOLDER AS IT PIVOTS. 